Antimicrobial Monomers

Antimicrobial activity is imparted to the surface(s) of an apparatus or article by polymerising tert-butylaminoethyl methacrylate in the presence of the apparatus or article to achieve adhesion of the polymer to the surface(s). The antimicrobial monomer is preferably graft polymerised on the surface(s). 

Biocidal polymers have been prepared from antimicrobial monomers or have been inspired from natural oligomers. Natural host defense peptides... 

Peculiar characteristics of chitins and chitosans are hemostatic action, anti-inflammatory effect, biodegradability, biocompatibihty, besides antimicrobial activity, retention of growth factors, release of glucosamine and M-acetylglucosamine monomers and oligomers, and stimulation of cellular activities [11,12,295-297]. 

Figure 4 Carajurone (R=CHs) and the related carajuretin (R=H) result by the very rapid enzymatic aerial oxidation of flavans present in the leaves of Arrabidaea chica. The plant is one of the most used Amazonian medicinal plants and the anti-microbial and other activities may be related to the presence of these red pigment. Some indigenous tribes use them as face paints and carajurone has been commercialised in the past as chica red. Genipa americana fruit juice, by the action of an endogenous glucosidase followed by aerial oxidation, provides another pigment. The juice has multiple medicinal uses probably associated with its antimicrobial action. Here the dye is blue-black and is believed to be an ethylene-bis- -aza-azulene , derived by condensation of the genipin monomer with primary amines. ...

There are few reports of antimicrobial activity for alkylpyridinium compounds. However, the numbers are difficult to compare since authors have been using different bacterial strains or fungi in their assays. Overall, it appears that monomers are superior in antimicrobial activity over to oligomers and polymers, but again, this is not a general rule. 

Details are given of the synthesis of new methacrylate monomers containing pendant quaternary ammortirrm moieties based on diazabicyclo-octane. The monomers were homopolymers using azobismethylpropionarrride dihydrochloride as initiator. The monomers and polymers were characterised by elemental analysis, TGA, DSC, FTIR and carbon 13 NMR. Antimicrobial activities were investigated against S.aureus and E.coli. 41 refs. 

A new class of antimicrobial polymers is described in which the microbiological activity is based on their special constitution, which comprises surface-located amino functional groups, and the three-dimensional stracture of the polymers. The antimicrobial efficacy is attributed only to the final polymer itself, not to leaching of low molec.wL additives or the initial monomers. The polymers are not soluble in water and do not leach from surfaces like low... 

The polymer, which has a broad antimicrobial spectmm and produces a sufficient antimicrobial effect after a short contact time, is obtained by homo- or copolymerising a phosphonium salt type vinyl monomer, such as 2-(methaciylic acid) ethyltri-n-octylphosphonium chloride. The contact lens and article for its care are scarcely affected by contamination with microorganisms while retaining excellent optical performance and processability. 

An antimicrobial polymerisable composition is described, comprising an ethylenically imsaturated monomer, a specific monomer having antimicrobial activity and polymerisation initiator. The composition gives, upon polymerisation, apolymer having permanent antimicrobial activity, which is very useful for medical articles, in particrrlar dental materials. 

The polymer is prepared by homo- or copolymerising a vinyl phosphonium salt monomer, such as 2-methacryloxyethyltri-n-octylphosphonium chloride and has a wide antimierobial spectram and a sufficient antimicrobial effect, even with a short contact time. The lens and lens care products exhibit excellent optical properties and processabihty. 

The occurrence in the olive pomace of unique oleuropein oligomers (14) with a degree of polymerization of up to five oleuropein monomers was reported by Cardoso et al. [27]. Their bioactivities have, however, not yet been studied. In fact, besides the evidence that olive phenolic compounds can have antioxidant, cardioprotective, antimicrobial, antihypertensive, anti-inflammatory, and chemo-preventive properties [26], the majority of the studies have focused on hydroxytyrosol (15). This compound has revealed remarkable pharmacological and antioxidant activities and thus has been further studied for its bioavaUability and metabolism in humans in order to establish its health-beneficial effects [29-31]. 

In some plant species, the production of stilbene monomers and oligomers has been shown to be associated with a variety of stress factors [2,112,120,121,122,123,124]. The stilbene 1 is one of the most commonly encountered of these stress metabolites. While 1 has been shown to exhibit rather modest antimicrobial properties, some of its oligomeric derivatives have demonstrated more potent phytoalexin activity [2,8,125,126]. 

An effective way to test eukaryotic cell toxicity is to study the haemolytic behaviour of a system. While not conclusive, haemolysis experiments are used to indicate the possibility of eukaryotic cell toxicity [50]. It was found that, at the highest concentration tested (3 mg/ml), minimal haemolysis was observed. The high selectivity of these polymers is attributed to the use of fully water-soluble monomers, which allow the incorporation of hydrophobic moieties while maintaining the water-solubility of the polymer. A common practice within the antimicrobial polymer community is to report polymer selectivity toward bacterial cells over eukaryotic cells as a ratio of... 

Peptides are long, continuous and unbranched chain polymers formed by the polymerisation of amino acid monomers. During the polymerisation process two units are linked together via a peptide bond (-CO-NH-), which is formed by the reaction of a carboxylic group (-COOH) of one amino acid and an amino group (-NHi) of another. Peptides naturally occur in animals and plants, and can also be synthesised in the laboratory. Peptides play a significant role in the prevention of bacterial infections and, to date, more than 5,000 antimicrobial peptides (AMP) have been discovered or synthesised. 

Pumyani and Singh [28] described the synthesis of iodine-containing quaternary amine methacrylate (QAMA) copolymers. The monomers were prepared via a two-step reaction i) the reaction of ethylene glycol dimethacrylate with piperazine in methanol at 35 °C and ii) the quaternisation of the synthesised monomer with 1-iodooctane. The antimicrobial activities of the QAMA-containing copolymers were evaluated against Escherichia coli and Staphylococcus aureus. 

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